@vindiesel / Instagram 1 / 12
@vindiesel / Instagram 1 / 12

Vin Diesel is still grieving the death of his friend Paul Walker. The "Fast & Furious" actor spoke about his late costar -- and how his passing has impacted him -- during an appearance on "Live! with Kelly and Michael" on Friday.

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"It's a heavy thing," Diesel said of Walker, who died in November of last year at the age of 40 in a fiery car crash in Santa Clarita, Calif. "I grew up in the bouncer world, and we lost people while we were bouncing. But the brotherhood in Paul Walker was something completely different."

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"We grew up in the business together, and we became famous together, and we represented the biggest franchise together. He was my partner," the 46-year-old continued. "I've been acting all my life and they don't teach you in acting, how to mourn someone and simultaneously pretend they're in a scene with you."

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Walker's brothers Caleb and Cody were enlisted to complete scenes that featured Walker's character Brian O'Conner in Fast & Furious 7, which resumed filming after a four-month hiatus in March. Diesel bonded with the Walker brothers on set, and continued to post positive messages about his late friend via Facebook.

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The cast and crew wrapped production last month and celebrated with a Hollywood party on July 12. Leaving set, however, hasn't made Walker's death that much easier to deal with.

"It's one of the darker moments in this, in my journey," Diesel said to Ripa and Strahan. "It's a rough one."